Bitcoin, Litecoin and Monero, each for a reason.
Nexus accepts three coins, one more than most markets, and each answers a different need.
Monero is the privacy default, the coin to use when you do not want the payment legible on a public ledger. Litecoin is the small-order coin, faster and cheaper than Bitcoin when the network fee would be out of proportion to a modest purchase. Bitcoin is there for the vendors who still price in it.
Default to Monero unless a vendor forces otherwise. If you pay in Bitcoin, do not send straight from an identity-checked exchange, because that ties your name to the deposit. Route through a fresh wallet or swap into Monero first. Deposit addresses are issued fresh per order.
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